Devices that generate significant amounts of heat and/or operate under high-heat conditions, such as motors, electronic components, engines, exhaust systems, gearboxes, etc., often include cooling devices to reduce their operating temperature. Many cooling devices are configured to transfer thermal energy from a warmer object to a cooler object through conduction, convection, surface convection, or combinations thereof. Cooling devices often incorporate highly conductive materials and special structures, such as fins, to promote greater heat transfer. Coolants, such as air, water, refrigerants, and other fluids are also commonly used to improve the performance of cooling devices. Cooling devices that bring a coolant in direct contact with the device to be cooled are known as direct cooling devices.
Liquid cooling mediums, such as water, are often utilized in direct cooling devices due to their high capacity for heat transfer. Many cooling devices that utilize liquid coolants include a closed fluid circuit that allows reuse of the coolant. Seals, gaskets, and other materials are typically used at circuit connections to prevent leakage and contamination of the coolant. Heat sink structures, such as metal foams, have also been used in conjunction with liquid coolants for increasing the thermal connection between the coolant and the warm object. However, seals and gaskets can degrade over time and allow the liquid coolant to escape from the fluid circuit. As a result, some manufacturers avoid the use of all liquid coolants in applications where contact between leaked coolant and certain components of the warm object can cause significant damage. Also, heat sink structures can involve complicated manufacturing techniques and be costly to implement.
One attempt to improve heat transfer in a cooling device is described in U.S. Pat. No. 6,391,251 (“the '251 patent”) to Keicher et al. that issued on May 21, 2002. The '251 patent describes a method of forming an injection mold block having a mold cavity and cooling passages that are formed integrally with the injection mold block via a direct material deposition process. The cooling passages are located internally to the mold block at a uniform depth from a surface of the mold block to limit the cooing rate of material in the mold cavity. Adjacent cooling passages within the mold block form internal finned structures that increase the surface area of contact between the mold block and coolants within the passages.
Although the method of the '251 patent may be somewhat effective at forming internal cooling passages within a mold block, it may not be applicable for other types of cooling devices. In particular, the method of the '251 patent may not accommodate direct cooling of external objects or materials.
The cooling device of the present disclosure solves one or more of the problems set forth above and/or other problems of the prior art.